balloch



(No Model.) sneetsv-shever 1, G. R. BALLOCH. DIFFERENTIAL BICYCLE GEAR.

No. 593,450. Patented Nov. 9, 1897.

da f d (Nb Model.) 2 sheets-sheen 2.

G. R. BALLOCH. DIFFERENTIAL BICYCLE GEAR.

No. 593,450. Patented Nov. 9, 1897'.

i W' y UNITED STATES PATENT EEICE.

GUY R. BALLOCH, OF CNTREVILLE CANADA.

DIFFERENTIAL BICYCLE-G EAR.

SPECIFICATION forming partei Letters Patent No. 593,450, dated November e, 1897. @puatron filed :rupe 23,1897. semina. 641,914. oromodel.)

To all whom it may concern:

Be it known that I, GUY R. BALLOCH, of Centreville, in the Province of New Brunswick and Dominion of Canada, have invented a new and Improved Dierential Bicycle- Gear, of which the following'is a full, clear, and exact description.

The obj ect of the invention is to provide a new and improved dierential bicycle-gear which is simple and durable in construction and arranged to allow a rider to readily and conveniently change from a high gear to a low gear, or vice versa.

The invention consists principally of ahollow drive-wheel hub provided with differential gear-wheels, a double gear-wheel laterally slidable for meshing with either of the said hub gear-wheels, anda driven sprocketwheel in gear with the said double gear-wheel for rotating the latter within the hub and permitting lateral movement of the same.

The invention also consists of certain parts and details and combinations of the same, as will be fully described hereinafter and then pointed out in the claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters ofreference indicate corresponding parts in all the iigures.

Figure l is a longitudinal section of the hub of the drive-wheel containing the differential gear, the section being taken on the line 1 l of Fig. 2. Fig. 2 is a reduced side elevation of the improvement as applied with parts broken out and parts in section, and Fig. 3 is a plan view of part of the improvement.'

The hub A of the rear or drive wheel of the bicycle is made hollow and is mounted to turn at its sides on ball-bearings B B', of which the bearing B is supported from a hollow axle C and the other bearing B' is carried by a sprocket-wheel D, driven in the usual manner by the sprocket-chain from the crank-shaft of the bicycle, as is well known.v The sprocket-wheel D is mounted to turn on ball-bearings E E', supported from the hollow axle C, as is plainly illustrated in Fig. 1, so that the hub A and the sprocket-wheel D turn independently 0i' one another.

On the sides of the hub A and within the same are arranged beveled gear-wheels F F', preferably of different diameters, as is plainly indicated in Fig. l, and adapted tobe engaged by gear-wheels G G', respectively, forming a double gear-wheel mounted to rotate on ballbearings H, held on a disk I eccentric to the hollow axle C, as plainly indicated in Fig. l. Thus by the'arrangement described the gearwheel G is adapted to mesh with the gearwheel F at the upper end of the latter, while the large gear-wheel G' is adapted tomesh with the lower end of the gear-wheel F'.

' The double gear-wheel, composed of the gear-wheels G G', is rotated from the sprocket-wheel D,. and for this purpose the said double gear-wheel is formed with an internal gear-wheel G2, in mesh with a gear-wheel D', formed on an extension of the sprocket-wheel D, but rigidly connected with the same. The teeth of the internal gear-wheel G2 are of sufcient length to allow of sliding the double gear-wheel laterally in the hub A, so as to mesh with either of the gear-wheels F or F' without'moving the gear-Wheels D' and G2 out of mesh.

The disk I is fitted to slide transversely on the hollow axle C, and for this purpose I provide the hub of the said disk I with a pin I', ex-

tending through an elongated slot C', formed in the wall of the hollow axle C. The inner end of the pin I' is connected with a rod J, pressed on in a longitudinal direction by a spring J', so as to hold the rod J normally in an innermost position, with the disk I and gear-wheel G to the left and with the gearwheel G in mesh with the gear-wheel F.

The rod J extends through a cap C2 at one end of the hollow axle C, and on the outer threaded end of the said rod screws a nut J2, engaged by one end of a bell-crank lever K, fulcrumed at K' to a bracket L, held on the rear lower brace of the bicycle-frame, as is plainly indicated in Fig. 2. The other arm of this bell-crank lever K is engaged bythe upper end of a lever N, likewise fulcrumed on the bracket L and engaged at its lower end by a nut O', held on a rod O, pivotally connected with a lever P, fulcrumed at P on the crank-hanger of the bicycle, as is plainly shown in Fig. 2.

IOO

The lever P is provided with an arm P2, pivotally connected by a rod P3 and a nut P4 with a bell-crank lever Q, connected with a rod R, having a head R', the upper end of the said'rod being engaged by a spring-pressed hand-lever S, extending under the handle-bar and being under the control of the operator, the said rod being also telescopically adjustable. Thus when the rider presses the said lever S or releases the same a lateral sliding motion is given to the disk I to shift the double gear-wheel laterally and move the gearwheels G G' in and out of mesh with their rel spective gear-wheels F and' F'. The lever S is normally held in an outermost position by a spring T, somewhat stronger than the spring J,so that when the lever T is pressed upward toward the handle-grip then the spring J is released and is permitted to force the disk I and the double gear-wheel to the left to bring the wheel G in mesh with the wheel F. When the pressure on the lever S is released, then the spring T forces the said lever into an outermost position, whereby the rod J is pulled outward against the tension of the spring J', andthe double gear-wheel is shifted to the right to move the gear-wheels G and F out of mesh and the gear-wheels G F into mesh. It is evident that' byy the arrangement described a' high and low gear can be made use of wheneverV desired by the operator simply manipulating the lever S.

The difference in the size of the gears does not depend on a difference in the diameters of the gear-wheels G and G' or of the gearwheels F and F', but on a difference between the gear-wheels G and F and between the gear-wheels G and F. Gear-wheels F and F or wheels G and G' may have the same diameters. Of course if one pair have equal diameters the other pair will have more difference in their diameters than is shown in the drawings.

The entire device for transmitting motion to the drive-wheel is completely inclosed within the hollow hub A, and hence it is completely protected against dust and other impurities and is not liable to get out of order. Any suitable means may be employed for oiling the various parts.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1.- A differential bicycle-gear, comprising a hollow drive-wheel hub provided with differential gear-wheels, a double gear-wheel laterally slidable for meshing with either of the said hub gear-wheels, and a driven sprocketwheel in gear with the said double gear-wheel, for rotating the latter within the hub and permitting lateral movement of the saine, substantially as shown and described.

2. A dierential bicycle-gear, comprising a hollow drive-wheel hub provided with differential gear-wheels, a double gear-wheel laterally slidable for meshing with either of the said hub gear-wheels, a driven sprocketwheel in gear with the said double gear-wheel, for Vrotatin g the latter within the hub and permitting lateral movement of the same, and means, substantially as described, for shifting the said double gear-wheel laterally in the said hub, as set forth.

3. A differential bicycle-gear, comprising an axle, a slidable gear-wheel mounted eccentrically on the said axle, and formed with two gear-wheels of different diameters, means for rotating the said slidable gear-wheel from the driven sprocket-wheel, and gear-wheels on the hub of the drive-wheel, adapted to be engaged by the gear-wheels of the sai-d slidable gear-wheel, substantially as shown and described.

4. A differential bicycle-gear, comprising an axle, a slidable gear-wheel mounted eccentrically on the said axle, and formed with two gear-wheels, means for rotating the said slid-` able gear-wheel from the driven sprocketwheel, gear-wheels on lthe hub of the drivewheel, and adapted to be engaged by the gearwheels of the said slidable gear-wheel, adisk slidably held on the said axle and carrying a. bearing for the said slidable gear-wheel, and a spring-pressed rod connected with the said disk and extending within the said hollow axle, substantially as shown and described.

5. A differential bicycle-gear, comprising an axle, a slidable gear-wheel mounted eccentrically on the said axle, and formed with two gear-wheels, means for rotating the said slidable gear-wheel from the driven sprocketwheel, gear-wheels on the hub of the drivewheel, and adapted to be engaged bythe gearwheels of the said vslidable gear, a disk slidably held on the said axle and carrying abearing for the said slidable'gear-wheel, a springpressed rod connected with the said disk and yextending within the said hollow axle, and

means, substantially as described, for imparting movement to the said rod in one direction IOO IIO

from the handle-bar of the bicycle, as set i forth.

6. A differential bicycle-gear, comprising a hollow axle, a hollow drive-wheel hub concentric to the said axle, gear-wheels secured to the inside of the said hub at the sides thereof, a double beveled` gear-wheel fitted to slide laterally in the said hub, and adapted to mesh with either of the said hub gear-wheels, a disk 7. A differential bicycle-gear, comp'risingla` hollow axle, a hollow drive-wheel hub concentric to the said axle, gear-wheels secured to the inside of the said hub at the sides thereof, a double beveled gear-Wheel tted to slide double beveled gear-wheel, and means, sublaterally in lche said hub, and adapted to mesh stantially as described, for moving the said 4Io with et-her of the said hub gear-Wheels, a disk laterally on the said axle, as set forth.

disk fitted to slide on the said axle, and car- Tying the said double beveled gear-Wheel, a

sprocket-Wheel mounted to turn on thesaid axle, and having a gear-Wheel in mesh with an internal geanwh'eel formed on the said GUY R. BALLOCH.` 

